"The numbers 10 and 11 from Brodmann's ('09) map of primate cortex, emphasize the proximity of these frontal fields to the olfactory cor- tex. It is of note that both 10 and 11 share with the medial cortical region strong con- nections with the medial dorsal nucleus of the thalamus (Leonard, '69; Krettek and Price, '74a). "
" The character of fields 10 and 11 differs in important re- spects from that of the foregoing [other] frontal fields. In common with other fields along the dorsal shoulder of the rhinal fissure there is little distinction among cellular layers. The supragranular cortical zone of field 10 is uniformly globular without dis- tinction between layers I1 and 111. Though present, layer IV is narrow and of low cell density. Layer V is densely and more uni- formly cellular. The fiber density is low, comprising only a minimally developed stratum in layer VI and a few radial fibers. Field 11 is similar in its cell pattern to field 10, distinguished chiefly by a ten- dency of cells of the supragranular zone to be aggregated into clumps. Field 11 is dis- tinctive, however, for its high density pat- tern of radial fibers. "